The Journal of Environmentally Compatible Air Transport System (JECATS) is a not-for-profit international scientific journal dedicated to aspects of the air transport system with a focus on the environmental implications. JECATS combines areas of aerospace engineering, fuels, environmental analysis, climate change, economics, aviation climate mitigation, circularity and policy analysis. It includes aviation transport-related aspects and environmental effects from local to global scales.

It can be difficult to know if a given aircraft made a contrail. Existing methods that can be applied to any aircraft either use numerical weather data or satellite observations. In this work we create a new method by combining weather data and observations together. By comparison to in-situ measurements we show that the new method is superior to previous methods.

Targeted contrail avoidance consists of rerouting aircraft to minimise the formation of warming contrails. However, current predictions of contrail climate impact are highly uncertain. In this study, we show that some reroutings that were predicted to be beneficial for the climate are in fact damaging it. We further demonstrate that the risk of unintentionally damaging the climate can and should be included in the decision-making of contrail avoidance.

Lessening of non-CO₂ aviation impacts on climate is often accompanied by an increase of fuel consumption and emissions. Planning mitigation actions requires balancing the desired climate benefit against inevitable simultaneous climate damage. Due to uncertainty, statistical methods are needed to estimate the failure risk of concrete mitigation measures. This paper presents the required mathematics. 

Operational strategies such as eco-efficient flight routing have potential to reduce aviation’s climate effect. A collaborative workflow integrating weather forecast, climate response modelling, flight planning, air traffic control, and climate assessment was developed and tested in D-KULT. Innovative developments demonstrate substantial progress on how to identify alternative trajectories, highlighting remaining challenges with uncertainties in weather forecast and non-CO₂ climate effects.